Boring instrument.



PATENTED FEB. 7, 1905.

E. G. MUELLER.

BORING INSTRUMENT.

APPLICATION FILED we. 27,1904.

45 W I 5V .5 g, g l bi: m 2 m 1 6 w/ WITNESSES:

UNITED STATES Patented February 7, 1905.

PATENT OEEIcE.

EDI'VARD O. HUELLER, OF TOLEDO, OHIO, ASSIGNOR TO THE TOLEDO BUNG BUSHING COMPANY, OF TOLEDO, OHIO.

BORING INSTRUMENT.

SPECIFICATION forming part of Letters Patent No. 781,672, dated February 7, 1905.

Application filed August 27, 1904. Serial No. 222,383.

10 all Iv/mm, it non/y concern:

Be it known that I, EDWARD O. MUELLER, a citizen of the United States, residing at T0- ledo, in the county of Lucas and State of Ohio, have invented certain new and useful Improvements in Boring Instruments; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the figures of reference marked thereon, which form a part of this specification.

My invention relates to and its object is to provide an instrument for boring a diametrically-elongated hole. I attain this object by means of the devices and arrangement of parts hereinafter described, and shown and illustrated in the accompanying drawings, in whicl Figure 1 is a side elevation of my device; and Fig. 2, a transverse sectional plan view taken on line n a, Fig. 1.

In the drawings, 1 is a twist-bit having a threaded shank, (indicated by dotted lines in Fig. 1,) which threaded shank screws into the end of and is rigid with the taper reamer-carrier 3. This part is cylindrical in transverse section and at its lower end, to which the bit is secured, is tapered, as shown. The part 3 is longitudinally slotted at one side, as at 4, and this slot extends through and widens to a broad opening on the opposite side of the part 3, as at 5. (See Fig. 2.) The exterior of the part 3 is recessed to form a flat surface for the reception of a knife 6, the edge of which projects into the slot 4 and slightly beyond the curved exterior plane of the part 3. The knife is covered with a clamping-plate T, the exterior of which conforms to and corresponds with the cylindrical and tapered surface of the part 3. The plate 7 is secured in place by means of screws 8 passing through the plate and through elongated slots in the knife into screw-holes tapped into the part 3. In the body of the part 3 are small holes 9 in the plane of the knife 6. IV hen the screws 8 are loosened, a small instrument, such as an awl, may be inserted in the holes 9, and the knife may be forced outwardly, and the depth of its out may be thus regulated. At the end of the part 3 opposite the bit 1 is an axiallyprojecting shank 10. threaded to engage a handle or brace. At the lower end of the part 3 is a disk 11, having a central hole therethrough through which loosely passes the threaded shank 2 of the bit 1. This disk is of about the diameter of and corresponds in taper with the tapered extremity of the part 3. At the opposite end of the part 3 is another disk, 12, having a central hole therethrough through which passes the shank 10. 13 is a metal strip bent to conform to the longitudinal contour of the part 3 and curved transversely in the arc of a circle. At its opposite ends the piece 13 is secured, as at 1% 11, to the edges of the disks 11 12. The disks being loosely journaled on the shanks 2 10 and the two disks being rigidly connected by the piece 13, it will be seen that the knife-carrier 3 and the bit 1 are free to revolve independently of the connected parts 11 12 13.

The operation of my device is as follows: The shank 10 being suitably engaged with a proper brace or handle, a hole is bored, by means of the bit 1, through the board, plank, stave, or other object to be bored. The end pressure and rotation being continued, the disk 11 and the smaller end of the part 3 slip into the hole thus bored. Now the reamingknife comes in contact with one side of the auger-hole and at each revolution of the auger cuts away a shaving at one side of the hole, the shavings being discharged through the opening 5. At the opposite side of the hole the inclined guard-piece 13, which does not revolve, prevents the reamer from coming in contact with the wood and by its wedge-like action forces the cutting at the side of the hole opposite the piece 13. Thus as the tapered tool is forced deeper and deeper into the hole the cutting proceeds at one side of the hole only, thus forming an elongated hole approximately in the form of an ellipse. The length of the major axis of the ellipse will be determined by the angle of the tapered portion of the piece 13 to the axis of the tool.

Having described my invention, what I I0 which cuts in advance of the reamer, and a tapered guard for the reamer, loosely journaled on said body and adapted to enter the hole bored by the bit.

In testimony whereof I afiix my signature in presence of two Witnesses.

EDWARD C. MUELLER.

Witnesses JOHN L. DUNCAN, M. L. MARKS. 

